Wireless communication systems are widely deployed to provide various types of communication content such as voice, data, video, and the like, and deployments are likely to increase with introduction of new data oriented systems such as Long Term Evolution (LTE) systems. Wireless communication systems may be multiple-access systems capable of supporting communication with multiple users by sharing the available system resources (e.g., bandwidth and transmit power). Examples of such multiple-access systems include code division multiple access (CDMA) systems, time division multiple access (TDMA) systems, frequency division multiple access (FDMA) systems, 3GPP Long Term Evolution (LTE) systems, and other orthogonal frequency division multiple access (OFDMA) systems.
Generally, a wireless multiple-access communication system can simultaneously support communication for multiple wireless terminals (also know as user equipments (UEs), user terminals, or access terminals (ATs)). Each terminal communicates with one or more base stations (also know as access points (APs), EnodeBs, or eNBs) via transmissions on forward and reverse links. The forward link (also referred to as a downlink or DL) refers to the communication link from the base stations to the terminals, and the reverse link (also referred to as an uplink or UL) refers to the communication link from the terminals to the base stations. These communication links may be established via single-in-single-out, single-in-multiple out, multiple-in-single-out, or multiple-in-multiple-out (MIMO) systems.
Cellular wireless communications systems may include different types of cells providing access to communications networks, and many modern wireless terminals are capable of connecting to or camping on more than one type of cell. For example, wireless terminal may be capable of connecting to a Wireless Local Area Network (WLAN) cell or a cellular Radio Access Technology (RAT) (e.g., LTE). WLAN may be used interchangeably with “WiFi” and both may encompass or refer to IEEE 802.11 protocols. Cellular RATs may be further classified as Closed Subscriber Group (CSG) and non-CSG types. A CSG cell is limited to services a set of terminals associated with user accounts appearing in the CSG cell's access control list. A non-CSG cell does not use an access control list and may therefore service any terminal authorized by the operator (e.g., any subscriber or authorized roaming device). In many situations, more than one type of cell may be available to a terminal at any given time.
For example, in the Evolved Packet System (EPS), the Access Network Discovery and Selection Function (ANDSF) has defined methods for devices to determine which access technology is preferable for certain Internet Protocol (IP) traffic under specific condition, such as through the use of Inter-System Routing Policy (ISRP). ANDSF does not provide for methods to indicate preferences with granularity at the 3rd Generation Partnership Project (3GPP) RAT level within network policies. For example, it is not possible to distinguish between different types of cellular RATs and/or cells. This restricts the ability for the operator to provide policies that favor a specific 3GPP RAT over another one with reference to the WLAN preference. It would be desirable to remove this restriction for reasons that should be apparent from the disclosure that follows.